C# 操作SQL Server 公共库
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基本够用，存一下，以后找起来方便 public abstract class DB { //数据库连接字符串(config来配置) protected static string connectionString = ConfigurationManager.AppSettings["connectionString"]; public DB() { }
#region 公用方法 public static int GetMaxID(string FieldName, string TableName) { string strsql = "select max(" + FieldName + ")+1 from " + TableName; object obj = GetSingle(strsql); if (obj == null) { return 1; } else { return int.Parse(obj.ToString()); } }
public static bool Exists(string strSql, params SqlParameter[] cmdParms) { object obj = GetSingle(strSql, cmdParms); int cmdresult; if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { cmdresult = 0; } else { cmdresult = int.Parse(obj.ToString()); } if (cmdresult == 0) { return false; } else { return true; } } #endregion
#region 执行简单SQL语句
/// <summary> /// 执行SQL语句，返回影响的记录数 /// </summary> /// <param name="SQLString">SQL语句</param> /// <returns>影响的记录数</returns> public static int executeSql(string SQLString) { using (SqlConnection connection = new SqlConnection(connectionString)) { using (SqlCommand cmd = new SqlCommand(SQLString, connection)) { try { connection.Open(); int rows = cmd.executeNonQuery(); return rows; } catch (System.Data.SqlClient.SqlException E) { connection.Close(); Log.Error(E.Message + SQLString); return 0; } } } }
/// <summary> /// 执行多条SQL语句，实现数据库事务。 /// </summary> /// <param name="SQLStringList">多条SQL语句</param> public static void executeSqlTran(ArrayList SQLStringList) { using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; SqlTransaction tx = conn.BeginTransaction(); cmd.Transaction = tx; try { for (int n = 0; n < SQLStringList.Count; n++) { string strsql = SQLStringList[n].ToString(); if (strsql.Trim().Length > 1) { cmd.CommandText = strsql; cmd.executeNonQuery(); } } tx.Commit(); } catch (System.Data.SqlClient.SqlException E) { tx.Rollback(); throw new Exception(E.Message); } } }
/// <summary> /// 执行带一个存储过程参数的的SQL语句。 /// </summary> /// <param name="SQLString">SQL语句</param> /// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param> /// <returns>影响的记录数</returns> public static int executeSql(string SQLString, string content) { using (SqlConnection connection = new SqlConnection(connectionString)) { SqlCommand cmd = new SqlCommand(SQLString, connection); System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter("@content", SqlDbType.NText); myParameter.Value = content; cmd.Parameters.Add(myParameter); try { connection.Open(); int rows = cmd.executeNonQuery(); return rows; } catch (System.Data.SqlClient.SqlException E) { Log.Error(E.Message + SQLString); return 0; } finally { cmd.Dispose(); connection.Close(); } } }
/// <summary> /// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例) /// </summary> /// <param name="strSQL">SQL语句</param> /// <param name="fs">图像字节,数据库的字段类型为image的情况</param> /// <returns>影响的记录数</returns> public static int executeSqlinsertImg(string strSQL, byte[] fs) { using (SqlConnection connection = new SqlConnection(connectionString)) { SqlCommand cmd = new SqlCommand(strSQL, connection); System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter("@fs", SqlDbType.Image); myParameter.Value = fs; cmd.Parameters.Add(myParameter); try { connection.Open(); int rows = cmd.executeNonQuery(); return rows; } catch (System.Data.SqlClient.SqlException E) { Log.Error(E.Message + strSQL); return 0; } finally { cmd.Dispose(); connection.Close(); } } }
/// <summary> /// 执行一条计算查询结果语句，返回查询结果（object）。 /// </summary> /// <param name="SQLString">计算查询结果语句</param> /// <returns>查询结果（object）</returns> public static object GetSingle(string SQLString) { using (SqlConnection connection = new SqlConnection(connectionString)) { using (SqlCommand cmd = new SqlCommand(SQLString, connection)) { try { connection.Open(); object obj = cmd.executeScalar(); if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { return null; } else { return obj; } } catch (System.Data.SqlClient.SqlException e) { connection.Close(); Log.Error(e.Message + SQLString); return null; } } } }
/// <summary> /// 执行查询语句，返回SqlDataReader /// </summary> /// <param name="strSQL">查询语句</param> /// <returns>SqlDataReader</returns> public static SqlDataReader executeReader(string strSQL) { SqlConnection connection = new SqlConnection(connectionString); SqlCommand cmd = new SqlCommand(strSQL, connection); try { connection.Open(); SqlDataReader myReader = cmd.executeReader(); return myReader; } catch (System.Data.SqlClient.SqlException e) { throw new Exception(e.Message); } }
/// <summary> /// 执行查询语句，返回DataSet /// </summary> /// <param name="SQLString">查询语句</param> /// <returns>DataSet</returns> public static DataSet Query(string SQLString) { using (SqlConnection connection = new SqlConnection(connectionString)) { DataSet ds = new DataSet(); try { connection.Open(); SqlDataAdapter command = new SqlDataAdapter(SQLString, connection); command.Fill(ds, "ds"); } catch (System.Data.SqlClient.SqlException ex) { Log.Error(ex.Message + SQLString); return null; } return ds; } } #endregion
#region 执行带参数的SQL语句 /// <summary> /// 执行SQL语句，返回影响的记录数 /// </summary> /// <param name="SQLString">SQL语句</param> /// <returns>影响的记录数</returns> public static int executeSql(string SQLString, params SqlParameter[] cmdParms) { using (SqlConnection connection = new SqlConnection(connectionString)) { using (SqlCommand cmd = new SqlCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); int rows = cmd.executeNonQuery(); cmd.Parameters.Clear(); return rows; } catch (System.Data.SqlClient.SqlException E) { throw new Exception(E.Message); } } } }
/// <summary> /// 执行多条SQL语句，实现数据库事务。 /// </summary> /// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param> public static void executeSqlTran(Hashtable SQLStringList) { using (SqlConnection conn = new SqlConnection(connectionString)) { conn.Open(); using (SqlTransaction trans = conn.BeginTransaction()) { SqlCommand cmd = new SqlCommand(); try { //循环 foreach (DictionaryEntry myDE in SQLStringList) { string cmdText = myDE.Key.ToString(); SqlParameter[] cmdParms = (SqlParameter[])myDE.Value; PrepareCommand(cmd, conn, trans, cmdText, cmdParms); int val = cmd.executeNonQuery(); cmd.Parameters.Clear();
trans.Commit(); } } catch { trans.Rollback(); throw; } } } }
/// <summary> /// 执行一条计算查询结果语句，返回查询结果（object）。 /// </summary> /// <param name="SQLString">计算查询结果语句</param> /// <returns>查询结果（object）</returns> public static object GetSingle(string SQLString, params SqlParameter[] cmdParms) { using (SqlConnection connection = new SqlConnection(connectionString)) { using (SqlCommand cmd = new SqlCommand()) { try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); object obj = cmd.executeScalar(); cmd.Parameters.Clear(); if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value))) { return null; } else { return obj; } } catch (System.Data.SqlClient.SqlException e) { throw new Exception(e.Message); } } } }
/// <summary> /// 执行查询语句，返回SqlDataReader /// </summary> /// <param name="strSQL">查询语句</param> /// <returns>SqlDataReader</returns> public static SqlDataReader executeReader(string SQLString, params SqlParameter[] cmdParms) { SqlConnection connection = new SqlConnection(connectionString); SqlCommand cmd = new SqlCommand(); try { PrepareCommand(cmd, connection, null, SQLString, cmdParms); SqlDataReader myReader = cmd.executeReader(); cmd.Parameters.Clear(); return myReader; } catch (System.Data.SqlClient.SqlException e) { throw new Exception(e.Message); }
}
/// <summary> /// 执行查询语句，返回DataSet /// </summary> /// <param name="SQLString">查询语句</param> /// <returns>DataSet</returns> public static DataSet Query(string SQLString, params SqlParameter[] cmdParms) { using (SqlConnection connection = new SqlConnection(connectionString)) { SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, null, SQLString, cmdParms); using (SqlDataAdapter da = new SqlDataAdapter(cmd)) { DataSet ds = new DataSet(); try { da.Fill(ds, "ds"); cmd.Parameters.Clear(); } catch (System.Data.SqlClient.SqlException ex) { throw new Exception(ex.Message); } return ds; } } }
private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, string cmdText, SqlParameter[] cmdParms) { if (conn.State != ConnectionState.Open) conn.Open(); cmd.Connection = conn; cmd.CommandText = cmdText; if (trans != null) cmd.Transaction = trans; cmd.CommandType = CommandType.Text;//cmdType; if (cmdParms != null) { foreach (SqlParameter parm in cmdParms) cmd.Parameters.Add(parm); } } #endregion
#region 存储过程操作 /// <summary> /// 执行存储过程 /// </summary> /// <param name="storedProcName">存储过程名</param> /// <param name="parameters">存储过程参数</param> /// <returns>SqlDataReader</returns> public static SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters) { SqlConnection connection = new SqlConnection(connectionString); SqlDataReader returnReader; connection.Open(); SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters); command.CommandType = CommandType.StoredProcedure; returnReader = command.executeReader(); return returnReader; }
/// <summary> /// 执行存储过程 /// </summary> /// <param name="storedProcName">存储过程名</param> /// <param name="parameters">存储过程参数</param> /// <param name="tableName">DataSet结果中的表名</param> /// <returns>DataSet</returns> public static DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName) { using (SqlConnection connection = new SqlConnection(connectionString)) { DataSet dataSet = new DataSet(); connection.Open(); SqlDataAdapter sqlDA = new SqlDataAdapter(); sqlDA.selectCommand = BuildQueryCommand(connection, storedProcName, parameters); sqlDA.Fill(dataSet, tableName); connection.Close(); return dataSet; } }
/// <summary> /// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值) /// </summary> /// <param name="connection">数据库连接</param> /// <param name="storedProcName">存储过程名</param> /// <param name="parameters">存储过程参数</param> /// <returns>SqlCommand</returns> private static SqlCommand BuildQueryCommand(SqlConnection connection, string storedProcName, IDataParameter[] parameters) { SqlCommand command = new SqlCommand(storedProcName, connection); command.CommandType = CommandType.StoredProcedure; foreach (SqlParameter parameter in parameters) { command.Parameters.Add(parameter); } return command; }
/// <summary> /// 执行存储过程，返回影响的行数 /// </summary> /// <param name="storedProcName">存储过程名</param> /// <param name="parameters">存储过程参数</param> /// <param name="rowsAffected">影响的行数</param> /// <returns></returns> public static int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected) { using (SqlConnection connection = new SqlConnection(connectionString)) { int result; connection.Open(); SqlCommand command = BuildIntCommand(connection, storedProcName, parameters); rowsAffected = command.executeNonQuery(); result = (int)command.Parameters["ReturnValue"].Value; //Connection.Close(); return result; } }
/// <summary> /// 创建 SqlCommand 对象实例(用来返回一个整数值) /// </summary> /// <param name="storedProcName">存储过程名</param> /// <param name="parameters">存储过程参数</param> /// <returns>SqlCommand 对象实例</returns> private static SqlCommand BuildIntCommand(SqlConnection connection, string storedProcName, IDataParameter[] parameters) { SqlCommand command = BuildQueryCommand(connection, storedProcName, parameters); command.Parameters.Add(new SqlParameter("ReturnValue", SqlDbType.Int, 4, ParameterDirection.ReturnValue, false, 0, 0, string.Empty, DataRowVersion.Default, null)); return command; } #endregion } 该文章在 2023/8/22 15:20:24 编辑过 |
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